The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 17, 1987
Filed:
Nov. 21, 1985
John B Williams, Jr, Houston, TX (US);
Joy Manufacturing Company, Pittsburgh, PA (US);
Abstract
A gate valve 10 of slab gate variety with 'floating' seats having means for protecting the seat ring seals and seat pockets in severe operating conditions. Each seat ring (40,41) is provided in its rear face (43,44) with an annular groove (49) coaxial with the ring axis and of a diameter to be located closely adjacent the flow passage (16,17) through the valve and accommodating an O-ring seal (49,50) therein. A second annular groove (51) is formed in the outer cylindrical surface (40a, 41a) of the ring near the front face (43,44) of the ring and accommodates an O-ring seal therein. The two O-ring seals (49,52) and (50,51) by their location establish a 'trapped' volume chamber (55) behind the seat ring and seat pocket (32,33) which protects and isolates the seat pocket from corrosive ladings and solids deposition. Each seat ring is provided with an unobstructed 'bleed' passage (56) which extends from the front face of the ring to the rear face of the ring or other locations so as to open to the 'trapped' chamber whereby excessive pressure 'build-up' in the 'trapped' chamber as could damage the seat ring and seals or impair valve operation is precluded.